An Aircraft typically has various sections of their structure and/or interior cabin trim that incorporate thermal-acoustic packages for thermal insulation and reducing the noise that is transmitted into the cabin from outside of the fuselage, such as by the engines, the turbulent boundary layer over the fuselage, and the like, and that is directed inward to the aircraft cabin. For example, an aircraft with a metallic fuselage commonly has a layer of thermal-acoustic fibrous material interposingly positioned in the frame of the fuselage. The fibrous material helps to thermally insulate and reduce the noise passing through the fuselage to the aircraft cabin, providing a quieter, more comfortable and desirable environment for the passengers.
Recently, efforts to decrease the weight of an aircraft to improve fuel efficiency and lower emissions have led to the development of lower mass and higher stiffness aircraft structures, such as, for example, composite structures for the fuselage and the like. The lower mass and higher stiffness structures are structurally very efficient, but unfortunately result in a significant increase in the noise transmitted through the fuselage to the aircraft cabin. For instance, the noise level in an aircraft cabin enclosed in a composite fuselage resulting from outside noise can be about 10 dB or greater than the noise level in an aircraft cabin that is enclosed in a conventional metallic fuselage when both the composite and conventional fuselages utilize equivalent conventional thermal-acoustic packages.
Accordingly, it is desirable to provide a thermal-acoustic package for an aircraft with improved noise reducing efficacy. Moreover, it is desirable to provide a thermal-acoustic package for an aircraft that further reduces the noise transmitted through the fuselage into the aircraft cabin and the like. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background.